| 摘要 |
PURPOSE:To reduce the noise of a capacity coupling, suffering from an adjacent bit line by providing a dummy column select line, fixed to a constant voltage, between the adjacent column select lines, and forming the column and the dummy select lines by a wiring layer, different from the bit line. CONSTITUTION:A semiconductor memory device consists of plural word lines WLA1, WLB1, bit lines BLA0-BLA3, the inverse of BLA0- the inverse of BLA3, BLB0-BLB3, the inverse of BLB0- the inverse of BLB3, memory cell array blocks A, B consisting of memory cell groups, positioned at the points of intersection of above-mentioned lines, the column select lines CS0, CS1, the dummy column select lines DCS0, DCS1, fixed at a grounding potential. By providing the dummy column select line (DCS line), the capacity of the bit line comes as follows, C1+C2+C3' C1+C2+C3'+C4 and it increases strictly, but because the CS line and the DCS line are formed by the wiring layer, different from the bit line, it can be suppressed below a level, not to cause a trouble for a practical use, and the unbalance of a signal read-out quantity can be canceled as well. |
